Abstract: The solid-state power controller，which integrates the functions of traditional power distribution

devices such as circuit breakers and relays，is the core component of the all-electric aerospace vehicle power

distribution system.Among them，the inverse time overcurrent protection technology is one of the key technologies of solid-state power controllers，which is very important for the performance indicators and reliability of the power

distribution system. A new type of inverse time overcurrent protection circuit model was introduced，in which the

inverse delay protection was realized. Simulation was also made using Saber software to obtain the best circuit

parameters. In the end，experimental tests on the inverse time overcurrent protection characteristics was conducted to verify the effectiveness of the method.

      Key words: inverse time overcurrent protection ；solid state power controller（SSPC）；inverse time overcurrent protection curve